bkloppenborg's blog posts

Citizen Sky is now officially permanent part of the AAVSO. In the coming weeks we will be moving additional content to the AAVSO site and freezing this site as an archive of the 1st three years of the project. Please visit the new landing page for future updates.

As I have mentioned before, the instrument we used at IRTF is called SPEX. It is a medium resolution spectrograph. Specifically, it's a cross-dispersing spectrograph. What does this mean? Well, instead of dispersing light like a prism where the colors are all in one line, SPEX breaks the spectrally dispersed light into several orders that are displayed along side each other. I've included a copy of a figure I made for a previous presentation that includes SPEX data in LXD1.9 mode to give you an idea about the dispersion:

Picking up where I left off, in this blog post I will cover two topics: how we prepare for an observing session and how we conduct the observations.

How we prepare for an observing session.
The answer is short: meetings. Lots and lots of meetings. As part of our proposal we already specified our primary target (eps Aur) and verified that the instrument is capable of observing the star. We also specified at least one A0V star to use as a calibration star for telluric (atmospheric) line removal. In our final meetings, we double-check exposure times, calibration stars, and coordinates. During this time we finalize our observing plan by deciding the order in which we will observe the stars on our list and insert flats, darks, and arcs (all required for calibration) so that we can maximize our observing time.Read more

I decided to postpone my discussion of IRTF for one more day to announce something even cooler! The DSLR Documentation and Reduction team has released their first set of tutorials for general use. These tutorials walk you through how you can use your DSLR camera (or any other camera that can take RAW files) to do high-precision photometry, acheiving results of 0.01 or 0.001 mag precision!Read more

Before I entered graduate school, I had no idea about the complexity of research proposals, especially those in astronomy/astrophysics.

All telescope time for which I have applied has been peer reviewed. This means that my proposal is read by fellow astronomers/astrophysicists and evaluated against some scoring method. It is my responsibility, as the proposer, to convince the committee that not only is my research interesting, but also doable from a technical perspective.

During the 1983 eclipse something funny happened in the infrared spectrum. In addition to the continuum from the F-star, additional absorption lines started to appear. This doesn't seem that odd until one considers that some of the spectral lines, carbon monoxide (CO) in particular, did not appear until after mid-eclipse. The high resolution spectra obtained during the ecipse also provided some other interesting details, but I'll let you read the paper to find out those tidbits of information. (As an interesting sidenote, the integration times for these spectra were very long. One spectra i particular took 670 minutes! That's a little over 11 hours to get a single spectra!)Read more

This Tuesday night Dr. Stencel and I have four-hours of observing time on NASA's Infrared Telescope Facility (IRTF) during which we will be observing epsilon Aurigae in the infrared (0.8-5.0 micrometers). I thought this would be a perfect opportunity to offer you a glimpse of what a observing run is like at world-class research facility.

Over the next couple of days I'll be providing details about our observing session. I hope to cover these topics:

The chat transcript to the January 12, 2010 chat discussing the remaining questions after the exciting press releases at the AAS meeting is attached as a pdf document to this blog posting. It was really an exciting chat with several good questions being asked! The original chat advertisement follows:Read more

As noted by Jeff Hopkins in the Epsilon Aurigae Campaign newsletter and a recent Astronomer's Telegram, the eps Aur eclipse seems to have started later than was predicted by data from previous eclipses. What could be the cause of such a change? How could you confirm your theory?

The scientific process often begins with a thorough discussion of the problem and brainstorming solutions with colleagues. In an effort to start such dialog on Citizen Sky, I've started a forum to discuss the apparent shortening of the eclipse. I'm sure with several people discussing the topic, we will be able to solve this mystery.Read more